guddo
There are 210 households in a certain residential complex. All households in the complex that have more than one dog also have at least one cat. All households that have at least one cat have a pet rodent. How many households in the complex have a pet rodent?
(1) 18 households in the complex have two or more dogs.
(2) 90% of households in the complex that have a pet rodent have at least one cat.
A good CR-type question!
Statement 1(1) 18 households in the complex have two or more dogs.Based on the given information, we can deduce that a minimum of 18 households within the complex possess rodents as pets. This conclusion is drawn from Statement 1, which specifies that 18 households in the complex own two or more dogs. Additionally, considering the initial question premise, it is established that every household in the complex with multiple dogs also harbors at least one cat, and each household with a cat possesses a pet rodent. Consequently, we can affirm that the complex comprises a minimum of 18 households that own pet rodents.
However, we cannot conclude that ONLY 18 households have a pet rodent. The complex may include households with solely pet rodents or those with a combination of a pet rodent and one dog. Therefore, the statement alone is insufficient to definitively answer the question, leading us to eliminate options A and D.
Statement 2(2) 90% of households in the complex that have a pet rodent have at least one catThis statement furnishes details regarding households that possess a pet rodent, explicitly stating that all such households also possess a cat. Nevertheless, the initial information about the total number of households with a pet rodent is absent. Without this essential data, we lack the necessary foundation to find answers to the question asked. Therefore, this statement is insufficient.
CombinedThe combined statements fail to provide a conclusive answer as they do not eliminate the possibility that a household might exclusively have a rodent as a pet or could have another animal in addition to a rodent. The ambiguity persists, preventing us from definitively determining the composition of households with pet rodents.
Hence,
Option E